1 Introduction.

This is a power analysis on the CPUE sampling program for the Wampus Creek watershed. A summary of the number of locations sampled by year is found in Table 1.

Table 1. Summary of locations and fish captured by year
Year Locations BKTR BLTR BURB MNWH RNTR
2000 1 0 0 0 0 308
2007 3 86 0 0 21 293
2009 2 40 0 3 0 131
2011 2 37 0 0 0 137
2013 2 30 1 1 0 84
2015 2 43 0 1 0 156
2016 2 21 1 0 2 80

A preliminary plot of the CPUE over time for each of the species is found in Figure 1. Notice that even if the total number of fish captured is very small, there may many locations with imputed catches of 0 fish and so the plot may have many more points than expected.

2 Variance components

The variance components were estimated after fitting a linear mixed model to the CPUE on the logarithmic scale. A summary of the estimated variance components is found in Table 2.

Table 2 . Estimated variance components (log scale)
Species Sampling SD Process SD
BKTR 0.04 0.24
BLTR 0.03 0.01
BURB 0.64 0
MNWH 0 0
RNTR 0.01 0.59

3 Power analysis

A power analysis was conducted to detect a 10%, 30%, 50%, 100%, 200%, 300% change over 5 years by varying the number of sites given the sampling and process error estimated above. Results are summarized in Figure 2 (one plot per species).

4 Summary

Add text here summarizing the bleak results